Electronic reverse auctions (e-RAs) are considered to be an effective tool for negotiating tender prices and achieving cost savings. Furthermore, if multicritera evaluation is used, it can be expected that e-RAs will also contribute to achieving benefits in other areas, e.g. helping to minimize life-cycle costs. This study aims to analyse the mutual relationships between selected e-RA variables. More specifically, correlation analysis is applied to explore real e-RA data representing public tenders for construction work. This study’s findings reveal that the correlations examined are generally weak or very weak. Furthermore, it has been found that the value of correlation coefficients varies depending on the type of structure, and that public tenders are usually evaluated solely on the basis of the criterion of the lowest bid price. Recommendations for public authorities in using e-RAs in the role of the buyer are also provided at the end of this paper.

The occurrence of errors in publicworks tender documentation is an undesirable phenomenon which is unfortunately often encountered in construction practice. Errors may have various causes and also have varying levels of negative effects on the successful implementation of the investment project. Taking this fact into consideration, this paper aims to identify and assess errors in terms of the requirements laid down by the applicable legislation in the Czech Republic, especially the Public Procurement Act and the associated implementing decree. A total of 126 public tenders were analysed in detail from this perspective. The results show that the occurrence of particular errors is relatively high, especially with regard to the specification of the bill of quantities and the requirement to include references to openly accessible price systems. Furthermore, errors relating to the specification of the quantity of works, units of measurement and descriptions of cost items were identified as having the largest impact on a project. Findings presented in this paper aim to highlight common errors in public tender documents and raise awareness of the need to improve their quality to ensure legislative compliance.

The numerous overruns of the investor’s budget during tenders for the construction of railway infrastructure in Poland resulted in the widespread use of a new procedure for awarding public contracts – electronic auction. This procedure has many advantages and potential risks. One of the biggest benefits for an investor is the potential gains from reducing bids. Contractors competing against each other allow for the achievement of optimal prices for the planned construction investment. However, this may cause the originally calculated risks, should they materialize, lead to significant budget overruns. This, in turn, may imply further negative consequences, including exceeding the assumed investment deadlines. The article presents a method of modeling the influence of an electronic auction on a tender procedure with the use of a Bayesian network. Data from completed tender procedures announced by the PKP Polskie Linie Kolejowe S.A. were used to build the network. The created network was then validated, verified and calibrated using new data from 8 tender procedures.